Land Art , sometimes referred to as Earth Art or Earthworks , is a form of art which involves using physical landscapes to create art , taking art out of the museum and into the outside world.Modern Land Art movement really got going in the 1960s when American artists began creating Land Art on a large scale.Today , works of modern Land Art can be seen all over the world , sometimes right alongside much older pieces of Land Art created by people who lived thousands of years ago. Land Art , which is not necessarily unchangeable , can take a number of forms.For example , in 1970 Robert Smithson created the Spiral Jetty ( 螺旋状防波堤 ) , made of a collection of stones and mud , in the Great Salt Lake.The American artist made a large jetty in a spiral shape which sticks out into the waters of the lake. Reshaping the landscape is a common characteristic of Land Art , which can be created by moving parts around.People can also add things to the environment to create Land Art , like salt , which is added to the Spiral Jetty.It is possible to use plants.In all cases , Land Art is immovable. Land Art is designed to gradually form , change , and ually decay ( 衰落 ) . That’s one of the biggest differences between Land Art and most of the art one sees in the museums.Some works of art can exist only for a few hours or days.Others are exposed to rain and wind so that they develop and decay over time , which is part of the attractiveness in the eyes of the artists. 4 . What can be learned from the first paragraph? A . Land Art was the most popular art in the 1960s. B . Land Art aims to get people interested in nature. C . American artists were the first to create Land Art. D . People have been creating Land Art for thousands of years. 5 . What do we know about Robert Smithson? A . He is a great creative artist. B . He lives near the Great Salt Lake. C . He made the most famous Land Art. D . He was a pioneer in creating Land Art. 6 . One of the unique characteristics of Land Art lies in________. A . showing the extreme beauty of nature B . developing and decaying gradually over time C . combining the landscapes around completely D . offering the artists a chance to get close to nature 7 . What is the passage mainly about? A . Works of Land Art. B . History of Land Art. C . Changes of Land Art. D . Introduction of Land Art.